Hello Newbie. If I understand you correctly, your setup is a pretty standard one. You have a "core" switch that is at the heart of your operation which has VLAN's configured on it. Those VLAN's have IP addresses configured on them, and routing set up there.
Then you have a second "distribution" switch that you want to uplink to the core.
Getting these two to talk to each other is actually very simple. First - you would connect two ports together on these two devices. Leave that port on both devices in the "Default" VLAN, as untagged. On your distribution switch, create all the same VLAN's that are in use on your core switch (same tag numbers and same names). But do not put IP addresses on them at the distribution switch!
Then you need to tag the connecting ports between the two switches with all of the VLAN's that are in use at the distribution switch. The traffic will flow across that new pipe.
That's pretty much it. Now you can add devices to your distribution switch with whatever VLAN you want to use, with the port "untagged" for the chosen VLAN, and the traffic will carry over to your core. And you should be able to plug into any one of those ports on your distribution switch and ping the VLAN IP's on your core switch.
